<!DOCTYPE html>
<html lang="en-US">
<head>
  <title>CSS Reference: CSS 2.1 replaced element sizing</title>
  <link rel="author" title="L. David Baron" href="https://dbaron.org/">
  <meta name="flags" content="should"> <!-- undefinedness in 10.3.2 -->
  <style type="text/css">

  div { width: 200px }

  span {
    display: inline-block;
    width: 80px;
    height: 40px;
  }

  </style>
</head>
<body>

<div>
  <span style="background: black;"></span>, <!-- height-25-width-50 -->
  <span style="background: fuchsia;"></span>, <!-- height-25-ratio-2 -->
  <span style="background: silver;"></span>, <!-- width-50-ratio-2 -->
  <span style="background: blue; width: 300px"></span>, <!-- height-25-no-ratio -->
  <span style="background: orange; width: 50px; height: 150px"></span>, <!-- width-50-no-ratio -->
  <span style="background: gray; width: 200px; height: 100px"></span>, <!-- ratio-2 -->
  <span style="background: aqua; width: 300px; height: 150px"></span>. <!-- no-ratio -->

</div>

</body>
</html>
